<!DOCTYPE html>
<html lang="en">
<script src="include.js"></script>
<head>
    <style>
        body {
            margin: 0;
        }

        .scroll-container {
            height: 300px;
            width: 300px;
            overflow: auto;
            border: 2px solid #333;
            background-color: #f0f0f0;
        }

        .box {
            overflow: scroll;
        }

        .nested {
            border: 2px solid #777;
            background-color: white;
            height: 100px;
        }
    </style>
</head>
<body>
    <div class="scroll-container">
        <div class="box"><div class="nested">Box 1</div></div>
        <div class="box"><div class="nested">Box 2</div></div>
        <div class="box"><div class="nested">Box 3</div></div>
        <div class="box"><div class="nested">Box 4</div></div>
        <div class="box"><div class="nested">Box 5</div></div>
        <div class="box"><div class="nested">Box 6</div></div>
        <div class="box"><div class="nested">Box 7</div></div>
        <div class="box"><div class="nested">Box 8</div></div>
    </div>
</body>
<script>
    asyncTest(done => {
        const container = document.querySelector(".scroll-container");
        container.onscroll = () => {
            println(`new scrollY: ${container.scrollTop}`);
            done();
        };
        internals.wheel(50, 50, 0, 100);
    });
</script>
</html>